
I exclusively ride disc brake road bikes, so can this cheap AliExpress brake upgrade improve things or are they just overkill?
I have used disc brakes on my road bikes for many years at this point, and in all honesty, I have never felt like the brakes needed upgrading. The stock brakes are fine for 99% of road bikers, but I spotted some really cool looking brake calipers on AliExpress.
ZRace have just started selling flat mount 4 piston brake calipers on AliExpress, and as soon as I saw them, I had to buy them! 4 piston brakes have been available on mountain bikes for a while, but these are the first set of cheap flat mount 4 piston calipers I’ve come across, hence my excitement to test them.
Spoiler alert, these brakes are mental! SO much top end braking power, amazing modulation, and hitting brake fade is almost impossible, at least on the hill i’ve tested them on. A definite upgrade over the stock brakes, but do you really need them, and what are the drawbacks…?
Brake calipers - Affiliate link to the seller I used:
https://s.click.aliexpress.com/e/_oCynsEK
Yoeleo Altera Gravel bike:
https://www.yoeleobike.com/products/altera-g21-gravel-frameset
Timestamps:
00:00 – Overview
00:52 – Zrace 4 piston brakes
02:05 – Size and weight
02:57 – Phenolic resin pistons
03:52 – Why are more pistons better?
05:06 – Installation and testing
06:14 – Yoeleo gravel bike frame
07:39 – Testing stock brakes
09:49 – Installing 4 piston calipers
12:47 – Testing 4 piston calipers
14:38 – Are they overkill?
16:10 – Trade-offs
Intro roll:
Created by Dev Joshi - http://www.go2dev.co.uk
Instagram:
https://www.instagram.com/tracevelo/
Email:
tracevelouk@gmail.com
Please note:
I am not a professionally trained bike mechanic. There can be risks associated with using products that are unbranded, untested, or come from sources where the provenance is unknown. Please talk to a qualified bike mechanic if you are in any doubt.
In essence, be careful, do your research, and cycle safe!!!
Keywords: AliExpress Bike Upgrade,4 piston brakes,4 piston brake calieprs,4 piston brake calipers,zrace brake calipers,zrace brakes,road bike disc brake upgrade,road bike upgrade,brake upgrade,Road bike,cheap road bike upgrades,Chinese disc brakes,Cheap disc brakes,best road bike disc brakes,road bike disc brakes,4 piston,disc brake upgrade,Cheap chinese bike parts,AliExpress bike upgrades
Bike part mentions in this video
ZRACE XG4 Flat Mount 4 pistons Caliper, Road Hydraulic Brake Caliper, ICE-TECH Pads, BMX Raceing Caliper, Full CNC Lightweight
Created: May 21, 2025The reviewer discusses the ZRACE XG4 Flat Mount 4 pistons Caliper extensively throughout the video. They mention purchasing these calipers from AliExpress, noting their excitement about the four-piston design, which is unusual for road bikes. The reviewer highlights the calipers' lightweight CNC construction, flat mount compatibility, and the inclusion of ICE-TECH pads. They compare the design to Hope RX4 calipers but note the significant price difference. The reviewer installs the calipers, tests them extensively, and finds them to offer exceptional braking power and modulation, though they acknowledge the calipers are overkill for most road biking scenarios.
AI-Summary
Pros
- Exceptional braking power
- Improved modulation
- Lightweight CNC construction
- Flat mount compatibility for easy installation on road bikes
- Includes ICE-TECH pads
- Higher ceiling for brake fade resistance
- Good for heavier bike setups like bikepacking
- Better for loose and gravelly surfaces due to improved modulation
- Affordable compared to similar products like Hope RX4
Cons
- Complete overkill for most road biking scenarios
- Slightly softer initial brake pull due to larger piston surface area
- Twice the chance for piston seal failure compared to two-piston calipers
- Phenolic resin pistons may not be as durable as ceramic or aluminum
- Requires more careful bleeding process
Key Points
- Four-piston design
- Flat mount compatible
- ICE-TECH pads included
- Phenolic resin pistons
- Total piston surface area of 804 mm²
- Weighs 109g per caliper
- Uses same pad size as Hope RX4 calipers
- 6% increase in braking force compared to standard two-piston calipers


